#include<iostream>
using namespace std;
#include<vector>
class Solution {
public:
    bool isInterleave(string s1, string s2, string s3) {
        int n1 = s1.size(), n2 = s2.size();
        vector<vector<bool>> dp(n1 + 1, vector<bool>(n2 + 1));
        dp[0][0] = true;
        for (int i = 1; i <= n2; ++i)
            dp[0][i] = (dp[0][i-1]&&s2[i - 1] == s3[i - 1]);
        for (int i = 1; i <= n1; ++i)
            dp[i][0] = (dp[i-1][0]&&s1[i - 1] == s3[i - 1]);
        for (int i = 1; i <= n1; ++i) {
            for (int j = 1; j <= n2; ++j) {
                if ((dp[i][j - 1] && s2[j - 1] == s3[i + j - 1]) || (dp[i - 1][j] && s1[i - 1] == s3[i + j - 1]))
                    dp[i][j] = true;
            }
        }
        return dp[n1][n2];
    }
};
int main() {
    string str1("aabcc"), str2("dbbca"), str3("aadbbcbcac");
    Solution().isInterleave(str1, str2, str3);
}